ABSTRACT
The literature describing the larval development and metamorphosis of decapod crustaceans is reviewed for information concerning the feeding apparatus — the external mandibles and the internal gastric mill and filter of the stomach. The Caridea is the only group in which the masticating mandibles of the larvae are retained after metamorphosis and in which the gastric mill may be functionally reduced or absent in all postlarval stages. The Astacidea, Thalassinidea, and Palinura lack grinding mandibles, even in the larval stages. In the Dendrobranchiata, Anomura, and Brachyura, the function of mastication shifts from the mandibles to the stomach at metamorphosis. Anatomical changes in the feeding apparatus correspond to the changes in behavior, habitat, and diet that occur at metamorphosis.
